In some cases the latest transcription of something might not be the best. If you've seen a published book of tombstone inscriptions from the 1990s, you still might want to look at that book of transcriptions done in the 1940s. Stones might have been more legible in 1940, some might not have been readable at all in 1990.
That book of transcribed marriage records in the 1930s might contain handwriting interpretations with different renderings of certain words. The ink might not have been as faded in 1930 as it was when a later transcription was done. And the transcriptionist from 1930 might have been more familiar with local names than was the 1980 era transcriptionist.
Do not always assume the latest publication is the best. Sometimes it is not.